For the plum cream with slivovitz, soak the plums overnight, barely covered with water.
Bring the plums to a boil in the soaking water and cook over low heat until soft. Strain and drain.
Separate the eggs and mash the plums with the yolks and yogurt. Add the slivovitz and stir.
Beat the egg whites until stiff and stir into the plums.
Serve the plum cream with slivovitz well chilled.